Antenna



Feb. 6, 1945. c. R. FLEMING ANTENNA Patented Feb. 6, 1945 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to antennas for receiving or transmitting radio waves.

The object of the present inventio-n is to provide an antenna for short wave and broadcast frequency bands which increases the signal strength delivered to a receiver. Another object is to provide a simple and compact antenna for installation indoors on or near a receiver or outdoors on a support. Still another object is to provide an antenna which has'improved selectivity, and which decreases the static and other extraneous wave-lengths which may interfere with desired reception.

These and o-ther objects are attained by my invention which will be understood from the following description and the accompanying l drawing in whichfFig; 1 is a side elevational view showing my device, the insulating jacket of the teilolih and an inner V-shaped wire or rod l2, disposed in the same vertical plane, with the center portions of each brought together and twisted in two or three turns forming the twisted gether to form the assembly as shown. For the usual broadcast range, the outer prongs IIa and IIb are made about 17 inches long, and the inner prongs IZa and 12b are made about 14 inches long.

The center portions of the outer and inner Vs, when twisted, provide the center loops I5 and I6, to which are attached insulated lead wires Il and It, for connection to the terminals of the receiver or transmitter. The Iouter V is connected to the ground terminal, and the inner V to the aerial terminal.

For convenience in handling and protection, and in certain methods of mounting, I provide an insulating jacket I9, preferably of wood or plastic, which is provided with a threaded coupling 20 in its lower end, this coupling having inside threads 2| adapted for threaded attachment to a pipe, for convenience in fastening to an outdoor pipe mounting. The coupling is Iprovided with a slot 23 at its inner end so that it may be screwed into the jacket; and an opening 22 l.tlpfough which the lead wires I'I and I8 may project. The jacket I9 is adapted to slip over the twisted portion of the Vs, and to then be sealed in place by means of a plastic putty 24 or the like, or in other ways fastened on the twisted portion. A separator 25 is provided between the loops l5 and I6.

The twisted center portions of the Vs not only holds the parts together, but gives good mechanical strength to the device, and is also believed to act as a wave trap o-r filter to remove unwantportion I3, the wires or rods in this portion I each being electrically insulated as shown, the cuter V insulation being indicated as black and the inner V as green. The outer prongs IIa and I Ib are longer than the inner prongs I2a and I2b, and I have ioundthat this feature is important in giving optimum signal strength on reception. Eyelets are formed at the ends of the prongs, not only to prevent damage, or injury to persons, but also for supporting means when the device is hung o-n the wall or case of the receiver. The outer prongs IIa and IIb are preferably spaced at about 60 angle apart,vand the inner prongs I2@ and I2b are spaced symmetrically between the outer prongs with about 30 angle between them.v

I have found that this arrangement gives maximum improvement in the strength of a received radio signal.

The wires or rods forming my device are preferably of the usual circular cross-section, and of about 6 gauge or heavier, to give rigidity and 4strength when the center portions are twisted to vention only insofar as required by the prior art and the spirit of the appended claims.

I claim:

l. A four-pronged antenna comprising two rods forming outer and inner V-shaped members, respectively, with two outer and two inner prongs, the center portion of each member being electrically insulated and twisted together to form a rigid assembly, the four prongs being disposed in a single plane.

2. A four-pronged antenna comprising two rods forming outer and inner V-shaped memfor mounting the antenna on a, pipe support through which run said lead wires.

4. The device of claim 1, the said prongs being provided at their ends with mounting eyelets.

5. The device of claim 1 in which the outer prongs are longer than the inner prongs.

6. The device of claim 1, in which the outer prongs are positioned at about 30 degrees from the Vertical and the inner prongs are about l5 l0 degrees from the vertical.

CHARLES R. FLEMING. 

